Add ability to sync tags to remote mirror.

app/models/remote_mirror.rb

@@ -101,7 +101,7 @@ class RemoteMirror < ActiveRecord::Base
   end
 
   def full_url
-    mirror_url = Gitlab::ImportUrl.new(super, credentials: credentials)
+    mirror_url = Gitlab::ImportUrl.new(url, credentials: credentials)
     mirror_url.full_url
   end
 

app/models/repository.rb

@@ -217,6 +217,10 @@ class Repository
     gitlab_shell.fetch_remote(path_with_namespace, remote, forced: forced, no_tags: no_tags)
   end
 
+  def remote_tags(remote)
+    gitlab_shell.list_remote_tags(path_with_namespace, remote)
+  end
+
   def fetch_remote_forced!(remote)
     gitlab_shell.fetch_remote(path_with_namespace, remote, forced: true)
   end

app/services/projects/update_remote_mirror_service.rb

@@ -13,8 +13,11 @@ module Projects
           errors << "The following branches have diverged from their local counterparts: #{divergent_branches.to_sentence}"
         end
 
-        push_to_mirror if changed_branches.present?
-        delete_from_mirror if deleted_branches.present?
+        push_branches if changed_branches.present?
+        delete_branches if deleted_branches.present?
+
+        push_tags if changed_tags.present?
+        delete_tags if deleted_tags.present?
       rescue Gitlab::Shell::Error => e
         errors << e.message.strip
       end
@@ -28,6 +31,41 @@ module Projects
 
     private
 
+    def local_branches
+      @local_branches ||= repository.local_branches.each_with_object({}) do |branch, branches|
+        branches[branch.name] = branch
+      end
+    end
+
+    def remote_branches
+      @remote_branches ||= repository.remote_branches(mirror.ref_name).each_with_object({}) do |branch, branches|
+        branches[branch.name] = branch
+      end
+    end
+
+    def push_branches
+      default_branch, branches = changed_branches.partition { |name| project.default_branch == name }
+
+      # Push the default branch first so it works fine when remote mirror is empty.
+      branches.unshift(*default_branch)
+
+      repository.push_branches(project.path_with_namespace, mirror.ref_name, branches)
+    end
+
+    def delete_branches
+      repository.delete_remote_branches(project.path_with_namespace, mirror.ref_name, deleted_branches)
+    end
+
+    def deleted_branches
+      @deleted_branches ||= remote_branches.each_with_object([]) do |(name, branch), branches|
+        local_branch = local_branches[name]
+
+        if local_branch.nil? && project.commit(branch.target)
+          branches << name
+        end
+      end
+    end
+
     def changed_branches
       @changed_branches ||= local_branches.each_with_object([]) do |(name, branch), branches|
         remote_branch = remote_branches[name]
@@ -42,46 +80,51 @@ module Projects
       end
     end
 
-    def deleted_branches
-      @deleted_branches ||= remote_branches.each_with_object([]) do |(name, branch), branches|
-        local_branch = local_branches[name]
-
-        if local_branch.nil? && project.commit(branch.target)
+    def divergent_branches
+      remote_branches.each_with_object([]) do |(name, branch), branches|
+        if local_branches[name] && repository.upstream_has_diverged?(name, mirror.ref_name)
           branches << name
         end
       end
     end
 
-    def push_to_mirror
-      default_branch, branches = changed_branches.partition { |name| project.default_branch == name }
+    def local_tags
+      @local_tags ||= repository.tags.each_with_object({}) do |tag, tags|
+        tags[tag.name] = tag
+      end
+    end
 
-      # Push the default branch first so it works fine when remote mirror is empty.
-      branches.unshift(*default_branch)
+    def remote_tags
+      @remote_tags ||= repository.remote_tags(mirror.ref_name).each_with_object({}) do |(name, target), tags|
+        # We're only interested in tag references
+        # See: http://stackoverflow.com/questions/15472107/when-listing-git-ls-remote-why-theres-after-the-tag-name
+        next if name =~ /\^\{\}\Z/
 
-      repository.push_branches(project.path_with_namespace, mirror.ref_name, branches)
+        tags[name] = target
+      end
     end
 
-    def delete_from_mirror
-      repository.delete_remote_branches(project.path_with_namespace, mirror.ref_name, deleted_branches)
+    def push_tags
+      repository.push_branches(project.path_with_namespace, mirror.ref_name, changed_tags)
     end
 
-    def local_branches
-      @local_branches ||= repository.local_branches.each_with_object({}) do |branch, branches|
-        branches[branch.name] = branch
-      end
+    def delete_tags
+      repository.delete_remote_branches(project.path_with_namespace, mirror.ref_name, deleted_tags)
     end
 
-    def remote_branches
-      @remote_branches ||= repository.remote_branches(mirror.ref_name).each_with_object({}) do |branch, branches|
-        branches[branch.name] = branch
+    def changed_tags
+      @changed_tags ||= local_tags.each_with_object([]) do |(name, tag), tags|
+        remote_tag_target = remote_tags[name]
+
+        if remote_tag_target.nil? || (tag.target != remote_tag_target)
+          tags << name
+        end
       end
     end
 
-    def divergent_branches
-      remote_branches.each_with_object([]) do |(name, branch), branches|
-        if local_branches[name] && repository.upstream_has_diverged?(name, mirror.ref_name)
-          branches << name
-        end
+    def deleted_tags
+      @deleted_tags ||= remote_tags.each_with_object([]) do |(name, target), tags|
+        tags << name if local_tags[name].nil?
       end
     end
 

lib/gitlab/backend/shell.rb

@@ -41,6 +41,23 @@ module Gitlab
       true
     end
 
+    def list_remote_tags(name, remote)
+      output, status = Popen::popen([gitlab_shell_projects_path, 'list-remote-tags', "#{name}.git", remote])
+
+      raise Error, output unless status.zero?
+
+      # Each line has this format: "dc872e9fa6963f8f03da6c8f6f264d0845d6b092\trefs/tags/v1.10.0\n"
+      # We want to convert it to: [{ 'v1.10.0' => 'dc872e9fa6963f8f03da6c8f6f264d0845d6b092' }, ...]
+      tags_with_targets = output.lines.flat_map do |line|
+        target, path = line.strip!.split("\t")
+        name = path.split('/', 3).last
+
+        [name, target]
+      end
+
+      Hash[*tags_with_targets]
+    end
+
     # Fetch remote for repository
     #
     # name - project path with namespace